1. Field of the Invention
The present invention relates to an automatic signalling apparatus provided with a life boat or a life jacket.
2. Description of the Prior Art
In general, in the event of a shipwreck, the surviors escape the shipwreck by means of a lifeboat, which because of its small size and the vastness of the oceans is difficult for a rescue boat to find. Often the life boat is equipped only with optical or acoustical signalling devices, such as a signal flare with or without a parachute, a sun signalling mirror, a light, a whistle, etc. The use of these devices is left within the discretion of the crew, depending of course upon weather and sea conditions at the time of shipwreck.
Recently, in order to improve this problem, a rescue signalling apparatus using a radio signal has been proposed. This signalling apparatus employs FM sweep oscillations in the frequency band of a marine radar and functions as a repeater apparatus for automatically initiating a corresponding rescue signal upon receiving the pulse wave of the marine radar. However, the distressed persons could not note whether or not the rescue activity has been started.